Scientists at the Netherlands Institute
for Brain Research have developed an experimental therapy which enables
rats with a spinal cord lesion to partially recover from their paralysis.
Up until now not even the slightest degree of recovery was possible. PhD
student Bas Blits was part of this team.

The method uses a combination of
transplantation and gene therapy. For the transplantation, the researchers
implanted nerve cells cultured in vitro. The cells originated from the
nerves between the ribs where they could be missed. Following the transplantation
gene therapy has to further stimulate the growth and recovery of the damaged
nerve cells. This is done by means of growth stimulating molecules. These
neurotrophic factors are naturally present during, for example, the recovery
of nerves following a deep cut in the finger. Normally they are not present
in large enough quantities in the spinal cord. Over the next few years
the researchers will try to improve their therapy. PhD student Bas Blits
will continue his research (with sponsorship from the Netherlands Organisation
for Scientific Research) at the University of Miami, where he will also
attempt to implant stem cells instead of the used nerve cells from the
fore rib.

The researchers attempted to repair
three sorts of spinal cord damage in rats. The first, the dorsal, partial
hemisection is comparable to a knife stab in the back in humans. The two
most important neural tracts for voluntary movement are severed. In both
humans and rats the result is a paralysed lower body. In rats the result
is partially paralysed rear legs. After therapy the rat's walking improved.
It appeared that one of the two neural tracts slowly recovered.

The second spinal cord lesion examined
by the researchers was the complete transection at the height of the eighth
vertebra. The spinal cord is completely severed, comparable in humans to
a spinal cord lesion after a violent knife stab in the rib area. Also,
this type results in paralysis in the lower part of the body. After the
therapy the rat could make some movement with his hind limbs. The scientists
are still trying to clarify this because anatomical investigation demonstrated
that there was no recovery of the spinal cord lesion.

The third type of damage was ventral
root avulsion. In this model the outgoing nerve fibre is torn lose from
the spinal cord, for example during a serious motorbike accident. This
damage often results in the dying of the affected motor neurones. These
are large nerve cells which control movement. After the administration
of growth stimulating substances, it appeared that the motor neurones did
not die but neither did they regenerate and recover.

The research was funded by the Netherlands
Organisation for Scientific Research (NWO).

Note:

This story has been adapted from
a news release issued by Netherlands Organization For Scientific Research
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